Doris Clark, 81, the dead woman’s mother, was also arrested and charged with obstruction of justice.

Sebastian was charged with murder, abuse of a corpse and promoting prison contraband. A homemade handcuff key was discovered in Sebastian’s mouth while he was being booked into the county jail, the sheriff’s office said in a statement.

Susan Mayo, 60, was reported missing on June 17 by one of her other children. She had shared a home with Sebastian, deputies said.

Sebastian claimed to be a big fan of John Wayne Gacy, the serial killer who buried his victims under his house.

Gacy was executed in 1994. He was convicted of sexually torturing and murdering teenage boys and young men in Illinois.

During a three-month investigation, authorities said Sebastian refused to cooperate with investigators and had been arrested earlier this week for allegedly interfering with deputies trying to search his residence, Burch said.

After five hours of digging and sawing through the porch Wednesday, deputies found the metal container with a decomposing body inside, authorities said.